User manual

29Wattmeters

L3 L3

U U

Fig 4.4.2 Three-phase/balanced wires (T3FE)

connection diagram (PX 120 only)

3.4.1Specific reference conditions

DC: AC component < 0.1% of the DC signal

AC: - Sinusoidal signals

- PF = 1

- Frequency: 50 Hz

3.4.2 Active power measurements

1. Press the ON/OFF key: the first screen appears

2. Connect the measurement leads to the instrument’s current measurement terminals

(on the left), complying with the polarities indicated: red lead on the “+” terminal and

black lead on the “COM” terminal.

Connect the measurement leads to the instrument’s voltage measurement terminals

(on the right), complying with the polarities indicated: red lead on the “+” terminal

and black lead on the “COM” terminal.

Set up as indicated in the connection diagrams in Fig.4.4.1 (single phase) or Fig.4.4.2

(balanced three-phase, T3FE only PX 120), depending on the case, making sure if

possible that the maximum acceptable limits are not exceeded (see table below).

Range switching is automatic.

■■

■ Characteristics

Display range 1000 W 6 kW

Measuring range 10.00 W...999.9 W 1000 W...5999 kW

Accuracy 1% of reading ±2 cts 1% of reading ±2 cts

Accuracy for DC 2% of reading ±3 cts 2% of reading ±3 cts

Resolution 0.1 W 1 W

Display stability 5 counts in normal mode

2 counts in SMOOTH mode

Response time 400 ms in normal mode

of the display 3 s in single-phase, in SMOOTH mode

Note 1

The measurement of the active power is a signed measurement.

Above 6 kW +10%, the display indicates “OL”.

Note 2: In three-phase, the active power is only measured on the fundamental

components so it is only valid for sinusoidal signals.

Chapter III